Semiconductor device and method of forming conductive vias with trench in saw street

ABSTRACT

A semiconductor wafer has a plurality of semiconductor die separated by a peripheral region. A trench is formed in the peripheral region of the wafer. A via is formed the die. The trench extends to and is continuous with the via. A first conductive layer is deposited in the trench and via to form conductive TSV. The first conductive layer is conformally applied or completely fills the trench and via. The trench has a larger area than the vias which accelerates formation of the first conductive layer. A second conductive layer is deposited over a front surface of the die. The second conductive layer is electrically connected to the first conductive layer. The first and second conductive layers can be formed simultaneously. A portion of a back surface of the wafer is removed to expose the first conductive layer. The die can be stacked and electrically interconnected through the TSVs.

FIELD OF THE INVENTION

The present invention relates in general to semiconductor devices and,more particularly, to a semiconductor device and method of formingconductive vias with a trench in the saw street.

BACKGROUND OF THE INVENTION

Semiconductor devices are commonly found in modern electronic products.Semiconductor devices vary in the number and density of electricalcomponents. Discrete semiconductor devices generally contain one type ofelectrical component, e.g., light emitting diode (LED), small signaltransistor, resistor, capacitor, inductor, and power metal oxidesemiconductor field effect transistor (MOSFET). Integrated semiconductordevices typically contain hundreds to millions of electrical components.Examples of integrated semiconductor devices include microcontrollers,microprocessors, charged-coupled devices (CCDs), solar cells, anddigital micro-mirror devices (DMDs).

Semiconductor devices perform a wide range of functions such ashigh-speed calculations, transmitting and receiving electromagneticsignals, controlling electronic devices, transforming sunlight toelectricity, and creating visual projections for television displays.Semiconductor devices are found in the fields of entertainment,communications, power conversion, networks, computers, and consumerproducts. Semiconductor devices are also found in military applications,aviation, automotive, industrial controllers, and office equipment.

Semiconductor devices exploit the electrical properties of semiconductormaterials. The atomic structure of semiconductor material allows itselectrical conductivity to be manipulated by the application of anelectric field or through the process of doping. Doping introducesimpurities into the semiconductor material to manipulate and control theconductivity of the semiconductor device.

A semiconductor device contains active and passive electricalstructures. Active structures, including bipolar and field effecttransistors, control the flow of electrical current. By varying levelsof doping and application of an electric field or base current, thetransistor either promotes or restricts the flow of electrical current.Passive structures, including resistors, capacitors, and inductors,create a relationship between voltage and current necessary to perform avariety of electrical functions. The passive and active structures areelectrically connected to form circuits, which enable the semiconductordevice to perform high-speed calculations and other useful functions.

Semiconductor devices are generally manufactured using two complexmanufacturing processes, i.e., front-end manufacturing, and back-endmanufacturing, each involving potentially hundreds of steps. Front-endmanufacturing involves the formation of a plurality of die on thesurface of a semiconductor wafer. Each die is typically identical andcontains circuits formed by electrically connecting active and passivecomponents. Back-end manufacturing involves singulating individual diefrom the finished wafer and packaging the die to provide structuralsupport and environmental isolation.

One goal of semiconductor manufacturing is to produce smallersemiconductor devices. Smaller devices typically consume less power,have higher performance, and can be produced more efficiently. Inaddition, smaller semiconductor devices have a smaller footprint, whichis desirable for smaller end products. A smaller die size may beachieved by improvements in the front-end process resulting in die withsmaller, higher density active and passive components. Back-endprocesses may result in semiconductor device packages with a smallerfootprint by improvements in electrical interconnection and packagingmaterials.

The electrical interconnection between semiconductor packages can beaccomplished with conductive through silicon vias (TSVs) or through holevias (THVs). To form TSVs or THVs, a via is cut through thesemiconductor material or peripheral region around each semiconductordie. The vias are filled with an electrically conductive material, forexample, copper deposition through an electroplating process.

The TSV and THV formation involves considerable time for the via fillingdue to its small area. The fully-filled TSV can produce high stressbetween vias leading to cracking and lower reliability. The equipmentneeded for electroplating, e.g., plating bath, and sidewall passivationincreases manufacturing cost. In addition, voids may be formed withinthe vias, which causes defects and reduces reliability of the device.TSV and THV can be a slow and costly approach to make verticalelectrical interconnections in semiconductor packages. Theseinterconnect schemes also have problems with production yield, largepackage size, and process cost management.

SUMMARY OF THE INVENTION

A need exists to efficiently and cost effectively form conductive viasto electrically interconnect stacked semiconductor die. Accordingly, inone embodiment, the present invention is a method of making asemiconductor device comprising the step of providing a semiconductorwafer having a plurality of semiconductor die separated by a peripheralregion, forming a via partially through the semiconductor die, andforming a trench partially through the peripheral region of thesemiconductor wafer. The trench is continuous with the via. The methodfurther including the steps of forming an insulating layer in the trenchand via, depositing a first conductive layer over the insulating layerin the trench and via to form conductive TSV, and depositing a secondconductive layer over a front surface of the semiconductor die. Thesecond conductive layer is electrically connected between the firstconductive layer and a contact pad on the semiconductor die. The methodfurther includes the step of removing a portion of a back surface of thesemiconductor wafer opposite the front surface of the semiconductorwafer to expose the first conductive layer.

In another embodiment, the present invention is a method of making asemiconductor device comprising the steps of providing a semiconductorwafer having a plurality of semiconductor die separated by a peripheralregion, forming a via partially through the semiconductor wafer, andforming a trench partially through the peripheral region of thesemiconductor wafer. The trench is continuous with the via. The methodfurther includes the steps of depositing a first conductive layer in thetrench and via to form conductive vias, and depositing a secondconductive layer over a front surface of the semiconductor die. Thesecond conductive layer is electrically connected to the firstconductive layer. The method further includes the step of removing aportion of a back surface of the semiconductor wafer opposite the frontsurface of the semiconductor wafer to expose the first conductive layer.

In another embodiment, the present invention is a method of making asemiconductor device comprising the steps of providing a semiconductorwafer having a plurality of semiconductor die separated by a peripheralregion, forming a via partially through the semiconductor wafer, andforming a trench partially through the peripheral region of thesemiconductor wafer. The trench is continuous with the via. The methodfurther includes the steps of depositing a first conductive layer in thetrench and via to form conductive vias, and removing a portion of abackside of the semiconductor wafer to expose the first conductivelayer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a PCB with different types of packages mounted to itssurface;

FIGS. 2 a-2 c illustrate further detail of the representativesemiconductor packages mounted to the PCB;

FIGS. 3 a-3 j illustrate a process of forming conductive vias withpartially filled trench in a peripheral region of the die;

FIGS. 4 a-4 b illustrate the semiconductor device with conductive viasand RDL;

FIG. 5 illustrates vertically stacked semiconductor die electricallyconnected with conductive vias and RDL;

FIGS. 6 a-6 e illustrate a process of forming conductive vias by fullyplating the trench;

FIGS. 7 a-7 e illustrate another process of forming conductive vias withthe partially filled trench in the peripheral region of the die; and

FIG. 8 illustrates the semiconductor device with conductive vias andbackside RDL.

DETAILED DESCRIPTION OF THE DRAWINGS

The present invention is described in one or more embodiments in thefollowing description with reference to the figures, in which likenumerals represent the same or similar elements. While the invention isdescribed in terms of the best mode for achieving the invention'sobjectives, it will be appreciated by those skilled in the art that itis intended to cover alternatives, modifications, and equivalents as maybe included within the spirit and scope of the invention as defined bythe appended claims and their equivalents as supported by the followingdisclosure and drawings.

Semiconductor devices are generally manufactured using two complexmanufacturing processes: front-end manufacturing and back-endmanufacturing. Front-end manufacturing involves the formation of aplurality of die on the surface of a semiconductor wafer. Each die onthe wafer contains active and passive electrical components, which areelectrically connected to form functional electrical circuits. Activeelectrical components, such as transistors and diodes, have the abilityto control the flow of electrical current. Passive electricalcomponents, such as capacitors, inductors, resistors, and transformers,create a relationship between voltage and current necessary to performelectrical circuit functions.

Passive and active components are formed over the surface of thesemiconductor wafer by a series of process steps including doping,deposition, photolithography, etching, and planarization. Dopingintroduces impurities into the semiconductor material by techniques suchas ion implantation or thermal diffusion. The doping process modifiesthe electrical conductivity of semiconductor material in active devices,transforming the semiconductor material into an insulator, conductor, ordynamically changing the semiconductor material conductivity in responseto an electric field or base current. Transistors contain regions ofvarying types and degrees of doping arranged as necessary to enable thetransistor to promote or restrict the flow of electrical current uponthe application of the electric field or base current.

Active and passive components are formed by layers of materials withdifferent electrical properties. The layers can be formed by a varietyof deposition techniques determined in part by the type of materialbeing deposited. For example, thin film deposition may involve chemicalvapor deposition (CVD), physical vapor deposition (PVD), electrolyticplating, and electroless plating processes. Each layer is generallypatterned to form portions of active components, passive components, orelectrical connections between components.

The layers can be patterned using photolithography, which involves thedeposition of light sensitive material, e.g., photoresist, over thelayer to be patterned. A pattern is transferred from a photomask to thephotoresist using light. The portion of the photoresist patternsubjected to light is removed using a solvent, exposing portions of theunderlying layer to be patterned. The remainder of the photoresist isremoved, leaving behind a patterned layer. Alternatively, some types ofmaterials are patterned by directly depositing the material into theareas or voids formed by a previous deposition/etch process usingtechniques such as electroless and electrolytic plating.

Depositing a thin film of material over an existing pattern canexaggerate the underlying pattern and create a non-uniformly flatsurface. A uniformly flat surface is required to produce smaller andmore densely packed active and passive components. Planarization can beused to remove material from the surface of the wafer and produce auniformly flat surface. Planarization involves polishing the surface ofthe wafer with a polishing pad. An abrasive material and corrosivechemical are added to the surface of the wafer during polishing. Thecombined mechanical action of the abrasive and corrosive action of thechemical removes any irregular topography, resulting in a uniformly flatsurface.

Back-end manufacturing refers to cutting or singulating the finishedwafer into the individual die and then packaging the die for structuralsupport and environmental isolation. To singulate the die, the wafer isscored and broken along non-functional regions of the wafer called sawstreets or scribes. The wafer is singulated using a laser cutting toolor saw blade. After singulation, the individual die are mounted to apackage substrate that includes pins or contact pads for interconnectionwith other system components. Contact pads formed over the semiconductordie are then connected to contact pads within the package. Theelectrical connections can be made with solder bumps, stud bumps,conductive paste, or wirebonds. An encapsulant or other molding materialis deposited over the package to provide physical support and electricalisolation. The finished package is then inserted into an electricalsystem and the functionality of the semiconductor device is madeavailable to the other system components.

FIG. 1 illustrates electronic device 50 having a chip carrier substrateor PCB 52 with a plurality of semiconductor packages mounted on itssurface. Electronic device 50 may have one type of semiconductorpackage, or multiple types of semiconductor packages, depending on theapplication. The different types of semiconductor packages are shown inFIG. 1 for purposes of illustration.

Electronic device 50 may be a stand-alone system that uses thesemiconductor packages to perform one or more electrical functions.Alternatively, electronic device 50 may be a subcomponent of a largersystem. For example, electronic device 50 may be a graphics card,network interface card, or other signal processing card that can beinserted into a computer. The semiconductor package can includemicroprocessors, memories, application specific integrated circuits(ASICs), logic circuits, analog circuits, RF circuits, discrete devices,or other semiconductor die or electrical components.

In FIG. 1, PCB 52 provides a general substrate for structural supportand electrical interconnect of the semiconductor packages mounted on thePCB. Conductive signal traces 54 are formed over a surface or withinlayers of PCB 52 using evaporation, electrolytic plating, electrolessplating, screen printing, or other suitable metal deposition process.Signal traces 54 provide for electrical communication between each ofthe semiconductor packages, mounted components, and other externalsystem components. Traces 54 also provide power and ground connectionsto each of the semiconductor packages.

In some embodiments, a semiconductor device has two packaging levels.First level packaging is a technique for mechanically and electricallyattaching the semiconductor die to an intermediate carrier. Second levelpackaging involves mechanically and electrically attaching theintermediate carrier to the PCB. In other embodiments, a semiconductordevice may only have the first level packaging where the die ismechanically and electrically mounted directly to the PCB.

For the purpose of illustration, several types of first level packaging,including wire bond package 56 and flip chip 58, are shown on PCB 52.Additionally, several types of second level packaging, including ballgrid array (BGA) 60, bump chip carrier (BCC) 62, dual in-line package(DIP) 64, land grid array (LGA) 66, multi-chip module (MCM) 68, quadflat non-leaded package (QFN) 70, and quad flat package 72, are shownmounted on PCB 52. Depending upon the system requirements, anycombination of semiconductor packages, configured with any combinationof first and second level packaging styles, as well as other electroniccomponents, can be connected to PCB 52. In some embodiments, electronicdevice 50 includes a single attached semiconductor package, while otherembodiments call for multiple interconnected packages. By combining oneor more semiconductor packages over a single substrate, manufacturerscan incorporate pre-made components into electronic devices and systems.Because the semiconductor packages include sophisticated functionality,electronic devices can be manufactured using cheaper components and astreamlined manufacturing process. The resulting devices are less likelyto fail and less expensive to manufacture resulting in a lower cost forconsumers.

FIGS. 2 a-2 c show exemplary semiconductor packages. FIG. 2 aillustrates further detail of DIP 64 mounted on PCB 52. Semiconductordie 74 includes an active region containing analog or digital circuitsimplemented as active devices, passive devices, conductive layers, anddielectric layers formed within the die and are electricallyinterconnected according to the electrical design of the die. Forexample, the circuit may include one or more transistors, diodes,inductors, capacitors, resistors, and other circuit elements formedwithin the active region of semiconductor die 74. Contact pads 76 areone or more layers of conductive material, such as aluminum (Al), copper(Cu), tin (Sn), nickel (Ni), gold (Au), or silver (Ag), and areelectrically connected to the circuit elements formed withinsemiconductor die 74. During assembly of DIP 64, semiconductor die 74 ismounted to an intermediate carrier 78 using a gold-silicon eutecticlayer or adhesive material such as thermal epoxy. The package bodyincludes an insulative packaging material such as polymer or ceramic.Conductor leads 80 and wire bonds 82 provide electrical interconnectbetween semiconductor die 74 and PCB 52. Encapsulant 84 is depositedover the package for environmental protection by preventing moisture andparticles from entering the package and contaminating die 74 or wirebonds 82.

FIG. 2 b illustrates further detail of BCC 62 mounted on PCB 52.Semiconductor die 88 is mounted over carrier 90 using an underfill orepoxy-resin adhesive material 92. Wire bonds 94 provide first levelpacking interconnect between contact pads 96 and 98. Molding compound orencapsulant 100 is deposited over semiconductor die 88 and wire bonds 94to provide physical support and electrical isolation for the device.Contact pads 102 are formed over a surface of PCB 52 using a suitablemetal deposition such electrolytic plating or electroless plating toprevent oxidation. Contact pads 102 are electrically connected to one ormore conductive signal traces 54 in PCB 52. Bumps 104 are formed betweencontact pads 98 of BCC 62 and contact pads 102 of PCB 52.

In FIG. 2 c, semiconductor die 58 is mounted face down to intermediatecarrier 106 with a flip chip style first level packaging. Active region108 of semiconductor die 58 contains analog or digital circuitsimplemented as active devices, passive devices, conductive layers, anddielectric layers formed according to the electrical design of the die.For example, the circuit may include one or more transistors, diodes,inductors, capacitors, resistors, and other circuit elements withinactive region 108. Semiconductor die 58 is electrically and mechanicallyconnected to carrier 106 through bumps 110.

BGA 60 is electrically and mechanically connected to PCB 52 with a BGAstyle second level packaging using bumps 112. Semiconductor die 58 iselectrically connected to conductive signal traces 54 in PCB 52 throughbumps 110, signal lines 114, and bumps 112. A molding compound orencapsulant 116 is deposited over semiconductor die 58 and carrier 106to provide physical support and electrical isolation for the device. Theflip chip semiconductor device provides a short electrical conductionpath from the active devices on semiconductor die 58 to conductiontracks on PCB 52 in order to reduce signal propagation distance, lowercapacitance, and improve overall circuit performance. In anotherembodiment, the semiconductor die 58 can be mechanically andelectrically connected directly to PCB 52 using flip chip style firstlevel packaging without intermediate carrier 106.

FIGS. 3 a-3 j illustrate a process of forming conductive vias in aperipheral region around a semiconductor die. In FIG. 3 a, a pluralityof semiconductor die 122 is formed on semiconductor wafer 120 usingconventional integrated circuit processes as described above.Semiconductor die 122 each contain analog or digital circuitsimplemented as active and passive devices, conductive layers, anddielectric layers formed on active surface 124 and electricallyinterconnected according to the electrical design of the die. Forexample, the circuit may include one or more transistors, diodes, andother circuit elements formed within active surface 124 to implementbaseband analog circuits or digital circuits, such as digital signalprocessor (DSP), ASIC, memory, or other signal processing circuit.Semiconductor die 122 may also contain integrated passive devices (IPD),such as inductors, capacitors, and resistors, for radio frequency (RF)signal processing. Contact pads 126 electrically connect to active andpassive devices and signal traces in active area 124 of semiconductordie 122. Semiconductor die 122 are separated by saw street 128, whichconstitute a non-functional, peripheral region of the die, as shown inFIG. 3 b.

In FIG. 3 c, a saw blade or laser tool 130 cuts trench 132 into sawstreet 128 between semiconductor die 122. In addition, vias 134 are cutinto active region 124 of semiconductor die 122 using laser drilling oretching process, such as deep reactive ion etching (DRIE), as shown inFIG. 3 d. The cut-out area of trench 132 extends to and is continuouswith the cut-out area of vias 134. Trench 132 and vias 134 extend onlypartially through semiconductor wafer 120. In one embodiment, trench 132and vias 134 are cut to a depth of 10-100 micrometers (μm), given awafer thickness of 50-250 μm. More generally, trench 132 and vias 134are greater than 10 percent of the wafer thickness. Trench 132 has asignificantly larger area than via 134. Trench 132 and vias 134 can beformed simultaneously or with separate cutting operations. The walls oftrench 132 and vias 134 can be vertical or tapered.

In FIGS. 3 e and 3 f, an insulating layer 136 is formed in bottom andsidewalls of trench 132 and vias 134 using PVD, CVD, printing, spincoating, spray coating, sintering, or thermal oxidation. The insulatinglayer 136 can be one or more layers of silicon dioxide (SiO2), siliconnitride (Si3N4), silicon oxynitride (SiON), tantalum pentoxide (Ta2O5),aluminum oxide (Al2O3), or other material having similar insulatingproperties.

In FIGS. 3 g and 3 h, an electrically conductive layer 138 isconformally applied into trench 132 and vias 134 using a patterning anddeposition process. An electrically conductive layer 140 is also formedover active surface 124 of semiconductor die 122 using a patterning anddeposition process. Conductive layer 138 covers the bottom and sidewallsof trench 132 and vias 134. The portion of conductive layer 138 in vias134 constitutes conductive TSV. Conductive layer 140 operates as aredistribution layer (RDL) or runner to electrically connect conductivelayer 138 to contact pads 126. Conductive layers 138 and 140 are formedusing PVD, CVD, sputtering, electrolytic plating, electroless platingprocess, or other suitable metal deposition process. Conductive layers138 and 140 can be one or more layers of Al, Cu, Sn, Ni, Au, Ag, orother suitable electrically conductive material.

In FIGS. 3 i and 3 j, a portion of a back surface of semiconductor wafer120, opposite active surface 124, is removed by a back-grinding oretching process to singulate semiconductor wafer 120. The portion ofinsulating layer 136 and conductive layer 138 on the bottom of trench132 and vias 134 is removed by the back-grinding process to separatesemiconductor die 122 into individual semiconductor devices 144. Inaddition, a saw blade or laser cutting tool removes saw street 128,including the portion of conductive layer 138, to electrically isolateTSVs 146, as shown in FIG. 4 a and 4 b. FIG. 5 shows a plurality ofstacked semiconductor devices 144 electrically interconnected by TSVs146 and RDLs 140.

The simultaneous formation of conductive layer 140 and conductive layer138 in vias 134 to form TSVs 146 simplifies the manufacturing process.The larger area and lower aspect ratio of trench 132 accelerates theformation (e.g., plating) of conductive layer 138 to fill vias 134.Trench 132 also reduces void formation. TSVs 146 are formed along theedge of semiconductor die 122 to dissipate stress inside via 134 to theperipheral area.

FIGS. 6 a-6 e illustrate another process of forming conductive vias inthe peripheral region around the semiconductor die. The formation of thedevice follows a similar process as described in FIGS. 3 a-3 f. AfterFIG. 3 f, an electrically conductive layer 150 is formed in trench 132and vias 134 using a patterning and deposition process, as shown in FIG.6 a. Conductive layer 150 completely fills or fully plates trench 132and vias 134. The time required to completely fill or fully plate trench132 and vias 134 is minimal considering acceleration of the platingprocess due to the large area and low aspect ratio of the trench. Anelectrically conductive layer 152 is also formed over active surface 124of semiconductor die 122 using a patterning and deposition process, seeFIG. 6 b. Conductive layer 152 operates as an RDL or runner toelectrically connect conductive layer 150 to contact pads 126.Conductive layers 150 and 152 are formed using PVD, CVD, sputtering,electrolytic plating, electroless plating process, or other suitablemetal deposition process. Conductive layers 150 and 152 can be one ormore layers of Al, Cu, Sn, Ni, Au, Ag, or other suitable electricallyconductive material.

In FIG. 6 c, a portion of a back surface of semiconductor wafer 120,opposite active surface 124, is removed by a back-grinding or etchingprocess to expose conductive layer 150. Semiconductor wafer 120 is thensingulated through saw street 128 using a saw blade or laser tool 156 toseparate semiconductor die 122. The singulation of semiconductor wafer120 removes saw street 128, including the portion of conductive layer150, but leaves the portion of conductive layer 150 in vias 134 to formTSVs 154, as shown in FIGS. 6 d and 6 e.

FIGS. 7 a-7 e illustrate another process of forming conductive vias inthe peripheral region around the semiconductor die. The formation of thedevice follows a similar process as described in FIGS. 3 a-3 f. AfterFIG. 3 f, an electrically conductive layer 160 is conformally appliedinto trench 132 and vias 134 using a patterning and deposition process,as shown in FIGS. 7 a and 7 b. An electrically conductive layer 162 isalso formed over active surface 124 of semiconductor die 122 using apatterning and deposition process. Conductive layer 160 covers thebottom and sidewalls of trench 132 and vias 134. The portion ofconductive layer 160 in vias 134 constitutes TSVs. Conductive layer 162operates as an RDL or runner to electrically connect conductive layer160 to contact pads 126. Conductive layers 160 and 162 are formed usingPVD, CVD, sputtering, electrolytic plating, electroless plating process,or other suitable metal deposition process. Conductive layers 160 and162 can be one or more layers of Al, Cu, Sn, Ni, Au, Ag, or othersuitable electrically conductive material.

In FIG. 7 c, a portion of a back surface of semiconductor wafer 120,opposite active surface 124, is removed by a back-grinding or etchingprocess. The portion of conductive layer 160 on the bottom of trench 132and vias 134 remains in place. Semiconductor wafer 120 is thensingulated through saw street 128 using a saw blade or laser tool 168 toseparate semiconductor die 122, as shown in FIG. 7 d. The singulation ofsemiconductor wafer 120 removes saw street 128, including the portion ofconductive layer 160, but leaves the portion of conductive layer 160 invias 134 to form TSVs 164, as shown in FIGS. 7 d and 7 e.

FIG. 8 shows RDL 166 formed on a back surface of semiconductor die 122.RDL 166 is electrically connected to TSV 164.

The simultaneous formation of conductive layer 162 and conductive layer160 in vias 134 to form TSVs 146 simplifies the manufacturing process.The larger area and lower aspect ratio of trench 132 accelerates theformation (e.g., plating) of conductive layer 160 to fill vias 134.Trench 132 reduces void formation. TSVs 164 are formed along the edge ofsemiconductor die 122 to dissipate stress inside via 134 to theperipheral area.

While one or more embodiments of the present invention have beenillustrated in detail, the skilled artisan will appreciate thatmodifications and adaptations to those embodiments may be made withoutdeparting from the scope of the present invention as set forth in thefollowing claims.

1. A method of making a semiconductor device, comprising: providing asemiconductor wafer having a plurality of semiconductor die separated bya peripheral region; forming a plurality of vias partially through thesemiconductor die; forming a trench partially through the peripheralregion of the semiconductor wafer, the trench being continuous with thevias; forming an insulating layer in the trench and vias; depositing afirst conductive layer over the insulating layer in the trench and viasto form conductive through silicon vias (TSV); depositing a secondconductive layer over a front surface of the semiconductor die, thesecond conductive layer being electrically connected between the firstconductive layer and a contact pad on the semiconductor die; andremoving a portion of a back surface of the semiconductor wafer oppositethe front surface of the semiconductor wafer to expose the firstconductive layer.
 2. The method of claim 1, wherein the trench has alarger area than the vias which accelerates formation of the firstconductive layer.
 3. The method of claim 1, further including formingthe first and second conductive layers simultaneously.
 4. The method ofclaim 1, further including completely filling the trench with the firstconductive layer.
 5. The method of claim 1, further including: stackinga plurality of semiconductor die; and electrically interconnecting theplurality of semiconductor die through the TSV.
 6. The method of claim1, wherein the trench and vias are formed through at least 10 percent ofa thickness of the semiconductor wafer.
 7. The method of claim 1,further including singulating through the peripheral region to separatethe semiconductor die while leaving a portion of the first conductivelayer in the vias to form the conductive TSV.
 8. A method of making asemiconductor device, comprising: providing a semiconductor wafer havinga plurality of semiconductor die separated by a peripheral region;forming a plurality of vias partially through the semiconductor wafer;forming a trench partially through the peripheral region of thesemiconductor wafer, the trench being continuous with the vias;depositing a first conductive layer in the trench and vias to formconductive vias; depositing a second conductive layer over a frontsurface of the semiconductor die, the second conductive layer beingelectrically connected to the first conductive layer; and removing aportion of a back surface of the semiconductor wafer opposite the frontsurface of the semiconductor wafer to expose the first conductive layer.9. The method of claim 8, wherein the trench has a larger area than thevias which accelerates formation of the first conductive layer.
 10. Themethod of claim 8, further including singulating through the peripheralregion to separate the semiconductor die while leaving a portion of thefirst conductive layer in the vias to form the conductive vias.
 11. Themethod of claim 8, further including forming a third conductive layer ona backside of the semiconductor die, the third conductive layer beingelectrically connected to the conductive vias.
 12. The method of claim8, further including completely filling the trench with the firstconductive layer.
 13. The method of claim 8, further includingconformally applying the first conductive layer in the trench.
 14. Themethod of claim 8, further including: stacking a plurality ofsemiconductor die; and electrically interconnecting the plurality ofsemiconductor die through the conductive vias.
 15. The method of claim8, wherein the trench and vias are formed through at least 10 percent ofa thickness of the semiconductor wafer.
 16. A method of making asemiconductor device, comprising: providing a semiconductor wafer havinga plurality of semiconductor die containing an active region separatedby a non-active peripheral region; forming a plurality of vias throughthe semiconductor wafer partially within the active region and partiallywithin the non-active peripheral region; forming a trench along a lengthof the non-active peripheral region of the semiconductor wafer, thetrench being continuous with the vias; depositing a first conductivelayer in the trench and vias to form conductive vias; and removing aportion of a backside of the semiconductor wafer to expose the firstconductive layer.
 17. The method of claim 16, further including formingan insulating layer in the trench and vias.
 18. The method of claim 16,further including depositing a second conductive layer over a surface ofthe semiconductor die, the second conductive layer being electricallyconnected to the first conductive layer.
 19. The method of claim 16,wherein the trench has a larger area than the vias which acceleratesformation of the first conductive layer.
 20. The method of claim 18,further including forming the first and second conductive layerssimultaneously.
 21. The method of claim 16, further includingsingulating through the peripheral region to separate the semiconductordie while leaving a portion of the first conductive layer in the vias toform the conductive vias.
 22. The method of claim 16, further includingforming a third conductive layer on a backside of the semiconductor die,the third conductive layer being electrically connected to theconductive vias.
 23. The method of claim 16, further includingcompletely filling the trench with the first conductive layer.
 24. Themethod of claim 16, further including conformally applying the firstconductive layer in the trench.
 25. The method of claim 16, furtherincluding: stacking a plurality of semiconductor die; and electricallyinterconnecting the plurality of semiconductor die through theconductive vias.
 26. A method of making a semiconductor device,comprising: providing a semiconductor wafer having a plurality ofsemiconductor die containing an active region separated by a non-activeperipheral region; forming a plurality of vias through the semiconductorwafer partially within the active region; forming a trench through thenon-active peripheral region of the semiconductor wafer, the trenchbeing continuous with the vias; depositing a first conductive layer inthe trench and vias to form conductive vias; and removing a portion of abackside of the semiconductor wafer to expose the first conductivelayer.
 27. The method of claim 26, further including forming aninsulating layer in the trench and vias.
 28. The method of claim 26,further including depositing a second conductive layer over a surface ofthe semiconductor die, the second conductive layer being electricallyconnected to the first conductive layer.
 29. The method of claim 28,further including forming the first and second conductive layerssimultaneously.
 30. The method of claim 26, wherein the trench has alarger area than the vias which accelerates formation of the firstconductive layer.
 31. The method of claim 26, further includingsingulating through the peripheral region to separate the semiconductordie while leaving a portion of the first conductive layer in the vias toform the conductive vias.
 32. The method of claim 26, further includingforming a third conductive layer on a backside of the semiconductor die,the third conductive layer being electrically connected to theconductive vias.
 33. The method of claim 26, further includingcompletely filling the trench with the first conductive layer.
 34. Themethod of claim 26, further including conformally applying the firstconductive layer in the trench.
 35. The method of claim 26, furtherincluding: stacking a plurality of semiconductor die; and electricallyinterconnecting the plurality of semiconductor die through theconductive vias.